PACKING A PAUNCH: O.J. Simpson arrives in a Vegas courtroom yesterday — grayer and flabbier, but still bearing the same smug expression he wore during his trial on kidnapping charges five years ago. Photo: WireImage

(AP)

O.J. Simpson in 2008. (AP)

PACKING A PAUNCH: O.J. Simpson arrives in a Vegas courtroom yesterday — grayer and flabbier, but still bearing the same smug expression he wore during his trial on kidnapping charges five years ago. (
)

A bloated and jowly O.J. Simpson rolled into a Las Vegas courtroom yesterday, looking as if he had just spent four years at an all-you-can-eat buffet instead of a tough Nevada prison.

His new girth could be seen in the greasy double chin and man boobs he sported while going before a judge at the start of a five-day hearing he hopes will lead to the dismissal of his 2008 armed-robbery and kidnapping convictions.

“He’s gained a lot of weight,” said Thomas Scotto, a friend of Simpson. “He’s eating a lot of junk food. It’s commissary food.

“[He buys] cans of chili, potato chips and other snacks. I think he has a hot plate or something.

“He said to me, ‘I gained a lot of weight . . . The food in here sucks.’ ”

When the Juice first got to Nevada’s Lovelock Correctional Center in late 2008, he was a lot closer to his 210-pound playing weight. Then he started suffering from arthritis.

“The first year he was in there he was working out in the gym,” Scotto said. “He was the head guy in charge of the gym and baseball coach. He was doing stuff. His arthritis started kicking in. He stopped working out.”

Now the fallen football star just sits in his cell and scarfs down junk food because he can’t stand the taste of the prison cafeteria food.

“He’s eating commissary food,” Scotto said. “Food in there sucks.”

O.J. famously beat the rap for killing his wife, Nicole, and her friend Ron Goldman in 1994 — only to be found civilly liable for the knife slayings in 1997.

Simpson is hoping to convince a judge that his former attorney, Yale Galanter, put up an ineffective defense against charges he engineered an armed confrontation in 2007 at a Vegas hotel room against sports-memorabilia collectors who had OJ keepsakes.

The former Heisman Trophy winner was sentenced to nine to 33 years behind bars for the crime.